I test drove the Solo. Everyone seemed to see me and honk or wave. But that was likely the exception, just on that one street on a saturday. And yep, it was red....Mostly visibility to other drivers was the biggest concern to me with the Solo....... I know the same thing can be said with a standard motorcycle.....
I drive a silver 2020 Corolla. It needed some body work, so I had to rent a car. I rented a black Fiat 500. Just a little taller than the Solo;
And yep, I felt very disrespected driving that. People could see me for the most part, but definitely were more aggressive and other bad behaviors around that little car. A black Solo would be much worse I would guess, once they got used to them being around.
But just like motorcycle navigation, apply self-defence and assume nobody sees you. A small vehicle will allow more abuility to excape to empty corners of the roadway. Which you will need.